The phosphorus content of polymer compositions is important to achieving flame retardancy. High molecular weight polyphosphonamides often have poor solubility or miscibility in the host polymer, and due to their high melt viscosity, significantly detract from the melt processability of the host resin. When added to thermosetting polymers, a reduction in glass transition temperature (Tg), heat distortion temperature (HDT), and modulus often results. Additionally, adding high molecular weight polyphosphonamides to other polymers leads to a lower phosphorus content compared to using oligomers.
Amino terminated phosphonamide oligomers can react with a variety of monomers and oligomeric species to form copolymers. For example, they can be co-reacted with epoxy formulations to produce a flame retardant polymer in which the phosphonamide oligomer is chemically incorporated into the matrix via covalent bond formation. Likewise, the amino terminated phosphonamide oligomers can be used as reactants to form copolyamides, copolyureas, copolyimides and any other copolymers that can react with an amine functional group. Therefore, there is a need for phosphonamides prepared by any synthetic route that have reactive amino end groups at sufficient concentration to participate in bond forming reactions with other monomers or reactive species to form copolymers.